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The Response of Mnsb-Sb Composites to Isothermal Aging

Published online by Cambridge University Press:  15 February 2011

T. F. Marinis
Affiliation:
Bell Telephone Laboratories, Allentown, PA 18103
R. F. Sekerka
Affiliation:
Carnegie-Mellon University, Pittsburgh, PA 15213
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Abstract

An eutectic alloy of antimony and manganese was directionally solidified to produce a composite of cylindrical fibers of MnSb aligned in a Sb matrix. The fibers were about 3 microns in diameter by 1 millimeter long and occupied 30% of the composite volume. Isothermal aging caused the fibers to develop undulations that had an average wavelength of 1.74 + 0.45 times the fiber circumference. The Nichols' and Mullins' model of fiber spheroidization predicts an undulation wavelength of √2 times the fiber circumference, for interface diffusion control. The Coine model, for volume diffusion control, predicts a wavelength that approaches infinity for this fiber volume fraction. Our modeling efforts have shown that the predicted wavelength is quite sensitive to the assumed spatial correlation between nodes on adjacent fibers. We also found that the undulation growth rate achieves a broad maximum as a function of wavelength, which may account for the large standard deviation associated with our measurements.

Type
Research Article
Copyright
Copyright © Materials Research Society 1982

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References

REFERENCES

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